Crash when calculating decay of color octet into octets

So the issue seems to be that something is not correct within the decays.py file within your model.
Without the full model, I'll not be able to investigate more than that.

One work-around would be to remove that file from your UFO model (this will force the auto-width to be handled completely numerically rather than analytically)

Cheers,

Olivier

Dear Olivier,

thanks for your quick reply. I have uploaded the FeynRules files and corresponding Mathematica notebook here: https://www.dropbox.com/s/9f58egf57rb8p8l/CHVectors_feynrules.zip?dl=0

When running with the decays.py deleted, the width calculation runs without error.

But when I then use the resulting param card to generate the process I'm interested in,

generate p p > vo, vo > sig8 sig8

it crashes again. This is the content of the debug file:

#************************************************************
#* MadGraph5_aMC@NLO/MadEvent *
#* *
#* * * *
#* * * * * *
#* * * * * 5 * * * * *
#* * * * * *
#* * * *
#* *
#* *
#* VERSION 3.5.0 2023-05-12 *
#* *
#* The MadGraph5_aMC@NLO Development Team - Find us at *
#* https://server06.fynu.ucl.ac.be/projects/madgraph *
#* *
#************************************************************
#* *
#* Command File for MadEvent *
#* *
#* run as ./bin/madevent.py filename *
#* *
#************************************************************
generate_events run_01
Traceback (most recent call last):
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/madevent/sum_html.py", line 307, in read_results
    self.axsec, self.xerru, self.xerrc, self.nevents, self.nw,\
ValueError: not enough values to unpack (expected 10, got 5)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/extended_cmd.py", line 1543, in onecmd
    return self.onecmd_orig(line, **opt)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/extended_cmd.py", line 1492, in onecmd_orig
    return func(arg, **opt)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/madevent_interface.py", line 2403, in do_generate_events
    self.run_generate_events(switch_mode, args)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/common_run_interface.py", line 7639, in new_fct
    original_fct(obj, *args, **opts)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/madevent_interface.py", line 2601, in run_generate_events
    self.exec_cmd('refine %s' % nb_event, postcmd=False)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/extended_cmd.py", line 1572, in exec_cmd
    stop = Cmd.onecmd_orig(current_interface, line, **opt)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/extended_cmd.py", line 1492, in onecmd_orig
    return func(arg, **opt)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/interface/madevent_interface.py", line 3600, in do_refine
    x_improve.launch() # create the ajob for the refinment.
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/madevent/gen_ximprove.py", line 1050, in launch
    self.results = sum_html.collect_result(self.cmd,
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/madevent/sum_html.py", line 753, in collect_result
    P_comb.add_results(os.path.basename(G), path, mfactors[G])
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/madevent/sum_html.py", line 434, in add_results
    oneresult.read_results(filepath)
  File "/home/manu/tools/MG5_aMC_v3_5_0/madgraph/madevent/sum_html.py", line 316, in read_results
    raise Exception("Reported error: End code %s \n Full associated log: \n%s"\
Exception: Reported error: End code 3.0
 Full associated log:
 Process in group number 1
 A PDF is used, so alpha_s(MZ) is going to be modified
 Old value of alpha_s from param_card: 0.13000000000000003
  ****************************************

       NNPDFDriver version 1.0.3
   Grid: NNPDF23_lo_as_0130_qed_mem0.grid
  ****************************************
 New value of alpha_s from PDF nn23lo1: 0.13000000000000000
 Define smin to 640000.00000000000
 *****************************************************
 * MadGraph/MadEvent *
 * -------------------------------- *
 * http://madgraph.hep.uiuc.edu *
 * http://madgraph.phys.ucl.ac.be *
 * http://madgraph.roma2.infn.it *
 * -------------------------------- *
 * *
 * PARAMETER AND COUPLING VALUES *
 * *
 *****************************************************

  External Params
  ---------------------------------

 mdl_CV8P8P8 = 0.29999999999999999
 mdl_g8uL = 0.29999999999999999
 mdl_g8q = 0.29999999999999999
 mdl_g8uR = 0.29999999999999999
 mdl_yPS8 = 0.29999999999999999
 aEWM1 = 127.90000000000001
 mdl_Gf = 1.1663700000000000E-005
 aS = 0.13000000000000003
 mdl_ymb = 4.7000000000000002
 mdl_ymt = 172.00000000000000
 mdl_ymtau = 1.7769999999999999
 mdl_MZ = 91.187600000000003
 mdl_MTA = 1.7769999999999999
 mdl_MT = 172.00000000000000
 mdl_MB = 4.7000000000000002
 mdl_MH = 125.00000000000000
 mdl_m8 = 400.00000000000000
 mdl_MVo = 3000.0000000000000
 mdl_WZ = 2.4952000000000001
 mdl_WW = 2.0850000000000000
 mdl_WT = 1.5083359999999999
 mdl_WH = 4.0699999999999998E-003
 mdl_w8 = 1.4619000000000000
 mdl_WVo = 31.103490000000001
  Internal Params
  ---------------------------------

 mdl_MZ__exp__2 = 8315.1783937600012
 mdl_MZ__exp__4 = 69142191.720053151
 mdl_sqrt__2 = 1.4142135623730951
 mdl_MH__exp__2 = 15625.000000000000
 mdl_complexi = (0.0000000000000000,1.0000000000000000)
 mdl_aEW = 7.8186082877247844E-003
 mdl_MW = 79.824359746197842
 mdl_sqrt__aEW = 8.8422894590285753E-002
 mdl_ee = 0.31345100004952897
 mdl_MW__exp__2 = 6371.9284088904105
 mdl_sw2 = 0.23369913342182447
 mdl_cw = 0.87538612427783857
 mdl_sqrt__sw2 = 0.48342438232036300
 mdl_sw = 0.48342438232036300
 mdl_g1 = 0.35807170271074895
 mdl_gw = 0.64839716719502682
 mdl_vev = 246.22056907348590
 mdl_vev__exp__2 = 60624.568634871241
 mdl_lam = 0.12886689630821144
 mdl_yb = 2.6995322804122722E-002
 mdl_yt = 0.98791394091683138
 mdl_ytau = 1.0206529494239589E-002
 mdl_muH = 88.388347648318444
 mdl_I1b33 = (2.69953228041227219E-002,0.0000000000000000)
 mdl_I2b33 = (0.98791394091683138,0.0000000000000000)
 mdl_I3b33 = (0.98791394091683138,0.0000000000000000)
 mdl_I4b33 = (2.69953228041227219E-002,0.0000000000000000)
 mdl_ee__exp__2 = 9.8251529432049817E-002
 mdl_sw__exp__2 = 0.23369913342182450
 mdl_cw__exp__2 = 0.76630086657817542
  Internal Params evaluated point by point
  ----------------------------------------

 mdl_sqrt__aS = 0.36055512754639896
 mdl_G__exp__2 = (1.6336281798666927,0.0000000000000000)
  Couplings of CHVectors_v1_UFO
  ---------------------------------

         GC_1 = 0.60000E+00 0.00000E+00
        GC_15 = 0.00000E+00 0.30000E+00

 Collider parameters:
 --------------------

 Running at P P machine @ 13000.000000000000 GeV
 PDF set = nn23lo1
 alpha_s(Mz)= 0.1300 running at 2 loops.
 alpha_s(Mz)= 0.1300 running at 2 loops.
 Renormalization scale set on event-by-event basis
 Factorization scale set on event-by-event basis

 getting user params
Enter number of events and max and min iterations:
 Number of events and iterations 1000 5 3
Enter desired fractional accuracy:
 Desired fractional accuracy: 0.10000000000000001
Enter 0 for fixed, 2 for adjustable grid:
Suppress amplitude (0 no, 1 yes)?
 Using suppressed amplitude.
Exact helicity sum (0 yes, n = number/event)?
 Explicitly summing over helicities
Enter Configuration Number:
Running Configuration Number: 1
 Not subdividing B.W.
 Attempting mappinvarients 1 4
 Determine nb_t
 T-channel found: 0
 Completed mapping 4
 about to integrate 4 1000 5 3 4 1
 Using non-zero grid deformation.
  4 dimensions 1000 events 4 invarients 5 iterations 1 config(s), (0.99)
 Using h-tuple random number sequence.
 Error opening grid
 Using Uniform Grid! 16
 Using uniform alpha 1.0000000000000000
 Grid defined OK
 Masses: 0.000E+00 0.000E+00 0.400E+03 0.400E+03
 Set CM energy to 13000.00
 Mapping Graph 1 to config 1
 Determine nb_t
 T-channel found: 0
 Setting PDF BW 3 1 3000.0000000000000
 Transforming s_hat BW 5.3254437869822494E-002 5.5213295857988180E-004
Using random seed offsets 1 : 1
  with seed 30
 Ranmar initialization seeds 8292 9405

 ********************************************
 * You are using the DiscreteSampler module *
 * part of the MG5_aMC framework *
 * Author: Valentin Hirschi *
 ********************************************

  Particle 3 4
      Et > 0.0 0.0
       E > 0.0 0.0
     Eta < -1.0 -1.0
   xqcut: 0.0 0.0
d R # 3 > -0.0 0.0
s min # 3> 0.0 0.0
xqcutij # 3> 0.0 0.0
 No cut BW -1 1
     9000005 > 9000001 9000001 color 8 > 8 8
 failed for ipartupdate. Please retry without MLM/default dynamical scale
STOP 3

ls status:
input_app.txt
log.txt
run1_app.log

                              Run Options
                              -----------
               stdout_level : 20 (user set)

                         MadEvent Options
                         ----------------
     automatic_html_opening : False (user set)
        notification_center : True
                   run_mode : 2
              cluster_queue : None (user set)
               cluster_time : None (user set)
               cluster_size : 100
             cluster_memory : 100 (user set)
                    nb_core : 16 (user set)
          cluster_temp_path : None

                      Configuration Options
                      ---------------------
               pythia8_path : None (user set)
                  hwpp_path : None (user set)
                thepeg_path : None (user set)
                 hepmc_path : None (user set)
           madanalysis_path : None (user set)
          madanalysis5_path : None (user set)
            pythia-pgs_path : None (user set)
                    td_path : None (user set)
               delphes_path : None (user set)
        exrootanalysis_path : None (user set)
               syscalc_path : None (user set)
                 rivet_path : None
                  yoda_path : None
                     lhapdf : lhapdf-config
                 lhapdf_py2 : None
                 lhapdf_py3 : None
                    timeout : 60
              f2py_compiler : None
          f2py_compiler_py2 : None
          f2py_compiler_py3 : None
                web_browser : None
                 eps_viewer : None
                text_editor : None
           fortran_compiler : None
               cpp_compiler : None
                auto_update : 7 (user set)
               cluster_type : condor
      cluster_status_update : (600, 30)
           cluster_nb_retry : 1
         cluster_local_path : None
         cluster_retry_wait : 300
#************************************************************
#* MadGraph5_aMC@NLO *
#* *
#* * * *
#* * * * * *
#* * * * * 5 * * * * *
#* * * * * *
#* * * *
#* *
#* *
#* VERSION 3.5.0 2023-05-12 *
#* *
#* The MadGraph5_aMC@NLO Development Team - Find us at *
#* https://server06.fynu.ucl.ac.be/projects/madgraph *
#* *
#************************************************************
#* *
#* Command File for MadGraph5_aMC@NLO *
#* *
#* run as ./bin/mg5_aMC filename *
#* *
#************************************************************
set group_subprocesses Auto
set ignore_six_quark_processes False
set low_mem_multicore_nlo_generation False
set complex_mass_scheme False
set include_lepton_initiated_processes False
set gauge unitary
set loop_optimized_output True
set loop_color_flows False
set max_npoint_for_channel 0
set default_unset_couplings 99
set max_t_for_channel 99
set zerowidth_tchannel True
set nlo_mixed_expansion True
import model sm
define p = g u c d s u~ c~ d~ s~
define j = g u c d s u~ c~ d~ s~
define l+ = e+ mu+
define l- = e- mu-
define vl = ve vm vt
define vl~ = ve~ vm~ vt~
import model /home/manu/runarea/ch-vectors/ch-vectors/CHVectors_v1_UFO
generate p p > vo, vo > sig8 sig8
launch
######################################################################
## PARAM_CARD AUTOMATICALY GENERATED BY MG5 ####
######################################################################
###################################
## INFORMATION FOR CV8P8P8
###################################
BLOCK CV8P8P8 #
      1 3.000000e-01 # cv8p8p8
###################################
## INFORMATION FOR MASS
###################################
BLOCK MASS #
      5 4.700000e+00 # mb
      6 1.720000e+02 # mt
      15 1.777000e+00 # mta
      23 9.118760e+01 # mz
      25 1.250000e+02 # mh
      9000001 4.000000e+02 # m8
      9000005 3.000000e+03 # mvo
      1 0.000000e+00 # d : 0.0
      2 0.000000e+00 # u : 0.0
      3 0.000000e+00 # s : 0.0
      4 0.000000e+00 # c : 0.0
      11 0.000000e+00 # e- : 0.0
      12 0.000000e+00 # ve : 0.0
      13 0.000000e+00 # mu- : 0.0
      14 0.000000e+00 # vm : 0.0
      16 0.000000e+00 # vt : 0.0
      21 0.000000e+00 # g : 0.0
      22 0.000000e+00 # a : 0.0
      24 7.982436e+01 # w+ : cmath.sqrt(mz__exp__2/2. + cmath.sqrt(mz__exp__4/4. - (aew*cmath.pi*mz__exp__2)/(gf*sqrt__2)))
###################################
## INFORMATION FOR NPG8L
###################################
BLOCK NPG8L #
      1 3.000000e-01 # g8ul
###################################
## INFORMATION FOR NPG8Q
###################################
BLOCK NPG8Q #
      1 3.000000e-01 # g8q
###################################
## INFORMATION FOR NPG8R
###################################
BLOCK NPG8R #
      1 3.000000e-01 # g8ur
###################################
## INFORMATION FOR NPYPS8
###################################
BLOCK NPYPS8 #
      1 3.000000e-01 # yps8
###################################
## INFORMATION FOR SMINPUTS
###################################
BLOCK SMINPUTS #
      1 1.279000e+02 # aewm1
      2 1.166370e-05 # gf
      3 1.300000e-01 # as (note that parameter not used if you use a pdf set)
###################################
## INFORMATION FOR YUKAWA
###################################
BLOCK YUKAWA #
      5 4.700000e+00 # ymb
      6 1.720000e+02 # ymt
      15 1.777000e+00 # ymtau
###################################
## INFORMATION FOR QNUMBERS 9000001
###################################
BLOCK QNUMBERS 9000001 # sig8
      1 0 # 3 times electric charge
      2 1 # number of spin states (2s+1)
      3 8 # colour rep (1: singlet, 3: triplet, 8: octet)
      4 0 # particle/antiparticle distinction (0=own anti)
###################################
## INFORMATION FOR QNUMBERS 9000005
###################################
BLOCK QNUMBERS 9000005 # vo
      1 0 # 3 times electric charge
      2 3 # number of spin states (2s+1)
      3 8 # colour rep (1: singlet, 3: triplet, 8: octet)
      4 0 # particle/antiparticle distinction (0=own anti)
###################################
## INFORMATION FOR DECAY
###################################
DECAY 1 0.000000e+00 #
DECAY 2 0.000000e+00 #
DECAY 3 0.000000e+00 #
DECAY 4 0.000000e+00 #
DECAY 5 0.000000e+00 #
DECAY 6 1.508336e+00 #
DECAY 11 0.000000e+00 #
DECAY 12 0.000000e+00 #
DECAY 13 0.000000e+00 #
DECAY 14 0.000000e+00 #
DECAY 15 0.000000e+00 #
DECAY 16 0.000000e+00 #
DECAY 21 0.000000e+00 #
DECAY 22 0.000000e+00 #
DECAY 23 2.495200e+00 #
DECAY 24 2.085000e+00 #
DECAY 25 4.070000e-03 #
DECAY 9000001 1.461900e+00 #
      1.000000e+00 2 -6 6 # 1.4619

DECAY 9000005 3.110349e+01 #
      3.092161e-01 2 9000001 9000001 # 9.617699856
      1.151317e-01 2 -1 1 # 3.58099883095
      1.151317e-01 2 -2 2 # 3.58099883095
      1.151317e-01 2 -3 3 # 3.58099883095
      1.151317e-01 2 -4 4 # 3.58099883095
      1.151317e-01 2 -5 5 # 3.58099883095
      1.151253e-01 2 -6 6 # 3.58079976855

#*********************************************************************
# MadGraph5_aMC@NLO *
# *
# run_card.dat MadEvent *
# *
# This file is used to set the parameters of the run. *
# *
# Some notation/conventions: *
# *
# Lines starting with a '# ' are info or comments *
# *
# mind the format: value = variable ! comment *
# *
# To display more options, you can type the command: *
# update to_full *
#*********************************************************************
#
#*********************************************************************
# Tag name for the run (one word) *
#*********************************************************************
  tag_1 = run_tag ! name of the run
#*********************************************************************
# Number of events and rnd seed *
# Warning: Do not generate more than 1M events in a single run *
#*********************************************************************
  10000 = nevents ! Number of unweighted events requested
  0 = iseed ! rnd seed (0=assigned automatically=default))
#*********************************************************************
# Collider type and energy *
# lpp: 0=No PDF, 1=proton, -1=antiproton, *
# 2=elastic photon of proton/ion beam *
# +/-3=PDF of electron/positron beam *
# +/-4=PDF of muon/antimuon beam *
#*********************************************************************
     1 = lpp1 ! beam 1 type
     1 = lpp2 ! beam 2 type
     6500.0 = ebeam1 ! beam 1 total energy in GeV
     6500.0 = ebeam2 ! beam 2 total energy in GeV
# To see polarised beam options: type "update beam_pol"

#*********************************************************************
# PDF CHOICE: this automatically fixes alpha_s and its evol. *
# pdlabel: lhapdf=LHAPDF (installation needed) [1412.7420] *
# iww=Improved Weizsaecker-Williams Approx.[hep-ph/9310350] *
# eva=Effective W/Z/A Approx. [2111.02442] *
# edff=EDFF in gamma-UPC [eq.(11) in 2207.03012] *
# chff=ChFF in gamma-UPC [eq.(13) in 2207.03012] *
# none=No PDF, same as lhapdf with lppx=0 *
#*********************************************************************
     nn23lo1 = pdlabel ! PDF set
     230000 = lhaid ! if pdlabel=lhapdf, this is the lhapdf number
# To see heavy ion options: type "update ion_pdf"
#*********************************************************************
# Renormalization and factorization scales *
#*********************************************************************
 False = fixed_ren_scale ! if .true. use fixed ren scale
     False = fixed_fac_scale ! if .true. use fixed fac scale
 91.188 = scale ! fixed ren scale
 91.188 = dsqrt_q2fact1 ! fixed fact scale for pdf1
 91.188 = dsqrt_q2fact2 ! fixed fact scale for pdf2
 -1 = dynamical_scale_choice ! Choose one of the preselected dynamical choices
 1.0 = scalefact ! scale factor for event-by-event scales

#*********************************************************************
# Type and output format
#*********************************************************************
  False = gridpack !True = setting up the grid pack
  -1.0 = time_of_flight ! threshold (in mm) below which the invariant livetime is not written (-1 means not written)
  average = event_norm ! average/sum. Normalization of the weight in the LHEF
# To see MLM/CKKW merging options: type "update MLM" or "update CKKW"

#*********************************************************************
#
#*********************************************************************
# Phase-Space Optimization strategy (basic options)
#*********************************************************************
   0 = nhel ! using helicities importance sampling or not.
                             ! 0: sum over helicity, 1: importance sampling
   2 = sde_strategy ! default integration strategy (hep-ph/2021.00773)
                             ! 1 is old strategy (using amp square)
        ! 2 is new strategy (using only the denominator)
# To see advanced option for Phase-Space optimization: type "update psoptim"
#*********************************************************************
# Customization (custom cuts/scale/bias/...) *
# list of files containing fortran function that overwrite default *
#*********************************************************************
  = custom_fcts ! List of files containing user hook function
#*******************************
# Parton level cuts definition *
#*******************************
  0.0 = dsqrt_shat ! minimal shat for full process
#
#
#*********************************************************************
# BW cutoff (M+/-bwcutoff*Gamma) ! Define on/off-shell for "$" and decay
#*********************************************************************
  15.0 = bwcutoff ! (M+/-bwcutoff*Gamma)
 #*********************************************************************
 # Apply pt/E/eta/dr/mij/kt_durham cuts on decay products or not
 # (note that etmiss/ptll/ptheavy/ht/sorted cuts always apply)
 #*********************************************************************
   False = cut_decays ! Cut decay products
#*********************************************************************
# Standard Cuts *
#*********************************************************************
# Minimum and maximum pt's (for max, -1 means no cut) *
#*********************************************************************
 {} = pt_min_pdg ! pt cut for other particles (use pdg code). Applied on particle and anti-particle
 {} = pt_max_pdg ! pt cut for other particles (syntax e.g. {6: 100, 25: 50})
#
# For display option for energy cut in the partonic center of mass frame type 'update ecut'
#
#*********************************************************************
# Maximum and minimum absolute rapidity (for max, -1 means no cut) *
#*********************************************************************
 {} = eta_min_pdg ! rap cut for other particles (use pdg code). Applied on particle and anti-particle
 {} = eta_max_pdg ! rap cut for other particles (syntax e.g. {6: 2.5, 23: 5})
#*********************************************************************
# Minimum and maximum DeltaR distance *
#*********************************************************************
#*********************************************************************
# Minimum and maximum invariant mass for pairs *
#*********************************************************************
 {} = mxx_min_pdg ! min invariant mass of a pair of particles X/X~ (e.g. {6:250})
 {'default': False} = mxx_only_part_antipart ! if True the invariant mass is applied only
                       ! to pairs of particle/antiparticle and not to pairs of the same pdg codes.
#*********************************************************************
# Inclusive cuts *
#*********************************************************************
 0.0 = ptheavy ! minimum pt for at least one heavy final state
#*********************************************************************
# maximal pdg code for quark to be considered as a light jet *
# (otherwise b cuts are applied) *
#*********************************************************************
 4 = maxjetflavor ! Maximum jet pdg code
#*********************************************************************
#
#*********************************************************************
# Store info for systematics studies *
# WARNING: Do not use for interference type of computation *
#*********************************************************************
   True = use_syst ! Enable systematics studies
#
systematics = systematics_program ! none, systematics [python], SysCalc [depreceted, C++]
['--mur=0.5,1,2', '--muf=0.5,1,2', '--pdf=errorset'] = systematics_arguments ! see: https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/Systematics#Systematicspythonmodule

Thanks Olivier Mattelaer, that solved my question.